Rotary wing systems with conventional tail rotors employ bearings which lower the reliability and increase the maintenance and life cycle costs to undesirable levels. Heretofore, a tail rotor with flapping (teetering) freedom having an elastic pitch beam has been tested, but encountered instability in the cyclic mode involving primarily flapping/chord bending. There exists a need for a composite tail rotor which eliminates pitch change bearings and which eliminates an instability heretofore encountered between flapping and first chord natural frequencies and in which there is achieved a separation between the first torsion and second beam natural frequencies.
Certain aspects of the invention disclosed herein are described in copending application Ser. No. 32,763, filed Apr. 24, 1979, entitled "Bearingless Tail Rotor for Helicopters", U.S. Pat. No. 4,306,837.